부산대학교 도서관

When an advanced non-intrusive optical technique of flow measurement is applied to a model test in a large water tunnel, it is hard to rapidly acquire the global information of the flow upon the model surface because of long imaging distance, light reflection from the model surface, imaging range-accuracy coupling, etc. Therefore, this study attempted to develop a technique of surface flow visualization suitable for high-speed inflow condition based on the multi-color ink tracing method, and then apply to the model tests conducted in the Large Cavitation Tunnel (LCT) of National Taiwan Ocean University (NTOU). This study first used the Median Cavitation Tunnel (MCT) of NTOU to find out the ink formula suitable for the high-speed inflow of 9.0 m/s, and then applied to a 1.5 m long, 6:1 prolate spheroid model tested in the LCT for verification; under AoA = -5.62∘and 9.0 m/s inflow, the test results successfully demonstrated that the laminar boundary layer was tripped by a turbulence stimulator to become turbulent, and a vortical flow structure was formed at the juncture region of the spheroid aft part and the sting.